Problem: Solve for $n$, $ \dfrac{n + 4}{5n + 9} = 6$
Answer: Multiply both sides of the equation by $5n + 9$ $ n + 4 = 6(5n + 9) $ $n + 4 = 30n + 54$ $4 = 29n + 54$ $-50 = 29n$ $29n = -50$ $n = -\dfrac{50}{29}$